Updating a register in memory

ABSTRACT

The present disclosure includes apparatuses and methods updating a register in memory. An example includes an array of memory cells; and a controller coupled to the array of memory cells configured to perform logical operations on data stored in the array of memory cells using a register that is updated to access the data stored in the array of memory cells.

TECHNICAL FIELD

The present disclosure relates generally to semiconductor memory and methods, and more particularly, to apparatuses and methods for updating a register in memory.

BACKGROUND

Memory devices are typically provided as internal, semiconductor, integrated circuits in computers or other electronic systems. There are many different types of memory including volatile and non-volatile memory. Volatile memory can require power to maintain its data (e.g., host data, error data, etc.) and includes random access memory (RAM), dynamic random access memory (DRAM), static random access memory (SRAM), synchronous dynamic random access memory (SDRAM), and thyristor random access memory (TRAM), among others. Non-volatile memory can provide persistent data by retaining stored data when not powered and can include NAND flash memory, NOR flash memory, and resistance variable memory such as phase change random access memory (PCRAM), resistive random access memory (RRAM), and magnetoresistive random access memory (MRAM), such as spin torque transfer random access memory (STT RAM), among others.

Electronic systems often include a number of processing resources (e.g., one or more processors), which may retrieve and execute instructions and store the results of the executed instructions to a suitable location. A processor can comprise a number of functional units such as arithmetic logic unit (ALU) circuitry, floating point unit (FPU) circuitry, and a combinatorial logic block, for example, which can be used to execute instructions by performing an operation on data (e.g., one or more operands). As used herein, an operation can be, for example, a Boolean operation, such as AND, OR, NOT, NAND, NOR, and XOR, and/or other operations (e.g., invert, shift, arithmetic, statistics, among many other possible operations). For example, functional unit circuitry may be used to perform the arithmetic operations, such as addition, subtraction, multiplication, and division on operands, via a number of operations.

A number of components in an electronic system may be involved in providing instructions to the functional unit circuitry for execution. The instructions may be executed, for instance, by a processing resource such as a controller and/or host processor. Data (e.g., the operands on which the instructions will be executed) may be stored in a memory array that is accessible by the functional unit circuitry. The instructions and/or data may be retrieved from the memory array and sequenced and/or buffered before the functional unit circuitry begins to execute instructions on the data. Furthermore, as different types of operations may be executed in one or multiple clock cycles through the functional unit circuitry, intermediate results of the instructions and/or data may also be sequenced and/or buffered. A sequence to complete an operation in one or more clock cycles may be referred to as an operation cycle. Time consumed to complete an operation cycle costs in terms of processing and computing performance and power consumption, of a computing apparatus and/or system.

In many instances, the processing resources (e.g., processor and associated functional unit circuitry) may be external to the memory array, and data is accessed via a bus between the processing resources and the memory array to execute a set of instructions. Processing performance may be improved in a processor-in-memory device, in which a processor may be implemented internally and near to a memory (e.g., directly on a same chip as the memory array). A processing-in-memory device may save time by reducing and eliminating external communications and may also conserve power.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a block diagram of an apparatus in the form of a computing system including a memory device in accordance with a number of embodiments of the present disclosure.

FIG. 1B is a block diagram in greater detail of the controller shown in FIG. 1A in accordance with a number of embodiments of the present disclosure.

FIG. 2 is a block diagram of a register in accordance with a number of embodiments of the present disclosure.

FIG. 3 is a block diagram of a set of resolve instructions in accordance with a number of embodiments of the present disclosure.

FIG. 4A is a block diagram illustrating a number of bit vectors (e.g., elements) stored as vertical elements in a memory array in accordance with a number of embodiments of the present disclosure.

FIG. 4B is a block diagram illustrating a number of bit vectors (e.g., elements) stored as horizontal elements in a memory array in accordance with a number of embodiments of the present disclosure.

FIG. 5 is a schematic diagram illustrating sensing circuitry to a memory device in accordance with a number of embodiments of the present disclosure.

FIG. 6 is a schematic diagram illustrating sensing circuitry to a memory device in accordance with a number of embodiments of the present disclosure.

FIG. 7 is a logic table illustrating selectable logic operation results implemented by a sensing circuitry in accordance with a number of embodiments of the present disclosure.

DETAILED DESCRIPTION

The present disclosure includes apparatuses and methods updating a register in memory. An example includes an array of memory cells and a controller coupled to the array of memory cells configured to perform logical operations on data stored in the array of memory cells using a register that is updated to access the data stored in the array of memory cells.

As described in more detail below, the register can include a reference that is updated and used to access data while performing logical operations on the memory device so the logical operation can access data based on the location of the data in the memory array and can access data from multiple locations in the memory array. The reference in the register can be updated by executing an instruction, such as a resolve instruction, for example, among other instructions that can enable updating of the register. The resolve instruction can update the reference in the register to iterate through data that is stored in a number of locations in the memory array. The transfer of reference information performed by a resolve instruction can be achieved without intervention by systems or processors other than a controller on the memory device. The resolve instruction can include fewer bits than a corresponding instruction executed on the host to access the same memory locations in the memory array. Subsequently, adjacent memory locations may be accessed by performing arithmetic operations on the bank register contents without intervention by systems or processors other than a controller on the memory device.

In the following detailed description of the present disclosure, reference is made to the accompanying drawings that form a part hereof, and in which is shown by way of illustration how one or more embodiments of the disclosure may be practiced. These embodiments are described in sufficient detail to enable those of ordinary skill in the art to practice the embodiments of this disclosure, and it is to be understood that other embodiments may be utilized and that process, electrical, and structural changes may be made without departing from the scope of the present disclosure.

As used herein, designators such as “X”, “Y”, “N”, “M”, etc., particularly with respect to reference numerals in the drawings, indicate that a number of the particular feature so designated can be included. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting. As used herein, the singular forms “a”, “an”, and “the” can include both singular and plural referents, unless the context clearly dictates otherwise. In addition, “a number of”, “at least one”, and “one or more” (e.g., a number of memory arrays) can refer to one or more memory arrays, whereas a “plurality of” is intended to refer to more than one of such things. Furthermore, the words “can” and “may” are used throughout this application in a permissive sense (i.e., having the potential to, being able to), not in a mandatory sense (i.e., must). The term “include,” and derivations thereof, means “including, but not limited to”. The terms “coupled” and “coupling” mean to be directly or indirectly connected physically or for access to and movement (transmission) of commands and/or data, as appropriate to the context. The terms “data” and “data values” are used interchangeably herein and can have the same meaning, as appropriate to the context.

The figures herein follow a numbering convention in which the first digit or digits correspond to the figure number and the remaining digits identify an element or component in the figure. Similar elements or components between different figures may be identified by the use of similar digits. For example, 150 may reference element “50” in FIG. 1A, and a similar element may be referenced as 450 in FIG. 4. As will be appreciated, elements shown in the various embodiments herein can be added, exchanged, and/or eliminated so as to provide a number of additional embodiments of the present disclosure. In addition, the proportion and/or the relative scale of the elements provided in the figures are intended to illustrate certain embodiments of the present disclosure and should not be taken in a limiting sense.

FIG. 1A is a block diagram of an apparatus in the form of a computing system 100 including a memory device 120 in accordance with a number of embodiments of the present disclosure. As used herein, a memory device 120, controller 140, memory array 130, sensing circuitry 150, logic circuitry 170, and/or cache 171 might also be separately considered an “apparatus.”

System 100 includes a host 110 coupled (e.g., connected) to memory device 120, which includes a memory array 130. Host 110 can be a host system such as a personal laptop computer, a desktop computer, a digital camera, a smart phone, or a memory card reader, among various other types of hosts. Host 110 can include a system motherboard and/or backplane and can include a number of processing resources (e.g., one or more processors, microprocessors, etc.). A more detailed diagram of one example of host 110 is described in association with FIG. 1C.

The system 100 can include separate integrated circuits or both the host 110 and the memory device 120 can be on the same integrated circuit. The system 100 can be, for instance, a server system and/or a high performance computing (HPC) system and/or a portion thereof Although the example shown in FIG. 1 illustrates a system having a Von Neumann architecture, embodiments of the present disclosure can be implemented in non-Von Neumann architectures, which may not include one or more components (e.g., CPU, ALU, etc.) often associated with a Von Neumann architecture.

For clarity, the system 100 has been simplified to focus on features with particular relevance to the present disclosure. The memory array 130 can be a DRAM array, SRAM array, STT RAM array, PCRAM array, TRAM array, RRAM array, NAND flash array, and/or NOR flash array, for instance. The array 130 can comprise memory cells arranged in rows coupled by access lines, which may be referred to herein as word lines and/or select lines, and columns coupled by sense lines, which may be referred to herein as data lines and/or digit lines. Although a single array 130 is shown in FIG. 1, embodiments are not so limited. For instance, memory device 120 may include a number of arrays 130 (e.g., a number of banks of DRAM cells, NAND flash cells, etc.). Additionally, although not shown, a plurality of memory devices 120 can be coupled to host 110 via a respective plurality of memory channels.

In various embodiments, the memory device 120 can be a bit vector operation device (e.g., a processing in memory (PIM) device). The memory device 120 includes address circuitry 142 to latch address signals provided over a bus 156 through I/O circuitry 144. Bus 156 can serve as a data bus (e.g., an I/O bus) and as an address bus; however, embodiments are not so limited. Status and/or exception information can be provided from the controller 140 on the memory device 120 to host 110 through a high speed interface (HSI), which can include an out-of-band bus 157. Address signals can be received through address circuitry 142 and decoded by a row decoder 146 and a column decoder 152 to access the memory array 130. Data can be read from memory array 130 by sensing voltage and/or current changes on the data lines using sensing circuitry 150. The sensing circuitry 150 can read and latch a page (e.g., row) of data from the memory array 130. The I/O circuitry 144 can be used for bi-directional data communication with host 110 over the data bus 156. The write circuitry 148 can be used to write data to the memory array 130.

Controller 140 decodes signals provided by control bus 154 from the host 110. These signals can include chip enable signals, write enable signals, and address latch signals that are used to control operations performed on the memory array 130, including memory operations (e.g., data read, data write, and/or data erase operations, among other operations, for example) and/or logical operations (e.g., AND, OR, and/or NOR operations, among other operations, for example). In various embodiments, the controller 140 is responsible for executing instructions from the host 110 and sequencing access to the array 130, among other functions. For example, executing instructions from host 110 can include performing operations (e.g., by executing microcode instructions) using processing resources corresponding to the sensing circuitry 150 and/or logic 170, as described further herein. The controller 140 can include a state machine (e.g., firmware and/or hardware in the form of an application specific integrated circuit (ASIC)), a sequencer, and/or some other type of controlling circuitry. In the example shown in FIG. 1A, the controller 140 includes a cache 171, which may store (e.g., at least temporarily) microcode instructions in accordance with a number of embodiments described herein executable (e.g., by a processing resource associated with controller 140 and/or host 110) to perform operations. In the example shown in FIG. 1A, the controller 140 includes a register 136. Register 136 can include a reference to data stored in the memory array 130. The reference in register 136 can be an operand in logical operations performed on the memory device 120. The reference in register 136 can updated while performing logical operations so that data stored in the memory array 130 can be accessed. A more detailed diagram of one example of controller 140 is described in association with FIG. 1B.

As described further below, in a number of embodiments, the sensing circuitry 150 can comprise a number of sense amplifiers and a number of compute components, which may serve as, and be referred to herein as an accumulator, and can be used to perform various operations (e.g., to perform logical operations on data associated with complementary sense lines). In a number of embodiments, storage locations (e.g., latches) corresponding to the compute components can serve as stages of a shift register. For example, clock signals can be applied to the compute components to shift data from one compute component to an adjacent compute component.

In a number of embodiments, the sensing circuitry 150 can be used to perform logical operations using data stored in array 130 as inputs and store the results of the logical operations back to the array 130 without transferring data via a sense line address access (e.g., without firing a column decode signal). As such, various compute functions can be performed using, and within, sensing circuitry 150 rather than (or in association with) being performed by processing resources external to the sensing circuitry (e.g., by a processor associated with host 110 and/or other processing circuitry, such as ALU circuitry, located on device 120 (e.g., on controller 140 or elsewhere)).

In various previous approaches, data associated with an operand, for instance, would be read from memory via sensing circuitry and provided to external ALU circuitry via I/O lines (e.g., via local I/O lines and/or global I/O lines). The external ALU circuitry could include a number of registers and would perform compute functions using the operands, and the result would be transferred back to the array via the I/O lines. In contrast, in a number of embodiments of the present disclosure, sensing circuitry 150 is configured to perform logical operations on data stored in memory array 130 and store the result back to the memory array 130 without enabling an I/O line (e.g., a local I/O line) coupled to the sensing circuitry 150. The sensing circuitry 150 can be formed on pitch with the memory cells of the array. Additional logic circuitry 170 can be coupled to the sensing circuitry 150 and can be used to store (e.g., cache and/or buffer) results of operations described herein.

As such, in a number of embodiments, circuitry external to array 130 and sensing circuitry 150 is not needed to perform compute functions as the sensing circuitry 150 can perform the appropriate logical operations to perform such compute functions without the use of an external processing resource. Therefore, the sensing circuitry 150 may be used to complement and/or to replace, at least to some extent, such an external processing resource (or at least the bandwidth consumption of such an external processing resource).

However, in a number of embodiments, the sensing circuitry 150 may be used to perform logical operations (e.g., to execute instructions) in addition to logical operations performed by an external processing resource (e.g., host 110). For instance, host 110 and/or sensing circuitry 150 may be limited to performing only certain logical operations and/or a certain number of logical operations.

Enabling an I/O line can include enabling (e.g., turning on) a transistor having a gate coupled to a decode signal (e.g., a column decode signal) and a source/drain coupled to the I/O line. However, embodiments are not limited to performing logical operations using sensing circuitry (e.g., 150) without enabling column decode lines of the array. Whether or not local I/O lines are used in association with performing logical operations via sensing circuitry 150, the local I/O line(s) may be enabled in order to transfer a result to a suitable location other than back to the array 130 (e.g., to an external register).

FIG. 1B is a block diagram in greater detail of the controller 140 shown in FIG. 1A in accordance with a number of embodiments of the present disclosure. In the example shown in FIG. 1B, the controller 140 is shown having control logic 131, sequencer 132, and timing circuitry 133 as part of a controller 140 of a memory device 120. Memory device 120 can include a controller 140 on each bank of the memory device and can be referred to as a bank process control unit (BPCU)

In the example of FIG. 1B, the memory device 120 may include a high speed interface (HSI) to receive data, addresses, control signals, and/or commands at the memory device 120. In various embodiments, the HSI may be coupled to a bank arbiter associated with the memory device 120. The HSI may be configured to receive commands and/or data from a host, e.g., 110 as in FIG. 1A. The bank arbiter may be coupled to the plurality of banks in the memory device 120.

In the example shown in FIG. 1B, the control logic 131 may be in the form of a microcoded engine responsible for fetching and executing machine instructions, e.g., microcode instructions, from an array of memory cells, e.g., an array as array 130 in FIG. 1A. The sequencer 132 may also be in the form of microcoded engines and/or ALU circuitry. Alternatively, the control logic 131 may be in the form of a very large instruction word (VLIW) type processing resource and the sequencers 132, and the timing circuitry 133 may be in the form of state machines and transistor circuitry.

The control logic 131 may receive microcode instructions from cache 171 and from may decode microcode instructions into function calls, e.g., microcode function calls (uCODE), implemented by the sequencers 132. The microcode function calls can be the operations that the sequencer 132 receives and executes to cause the memory device 120 to perform particular logical operations using the sensing circuitry such as sensing circuitry 150 in FIG. 1A. The timing circuitry 133 may provide timing to coordinate performance of the logical operations and be responsible for providing conflict free access to the arrays such as array 130 in FIG. 1A.

In the example shown in FIG. 1B, the sequencer 132 includes a register 136. Register 136 can include a reference to data stored in a memory array. The reference in register 136 can be used as an operand in logical operations performed on a memory device. The reference in the register 136 can be updated by iterating through indexes of the reference that access data stored in a memory array. For example, the reference can include a row index that is updated by iterating through a number of row indexes where a first row index is used to access data in a first row of a memory array and a second row index is used to access data in a second row of a memory array, and so on. The reference can be updated so that logical operations can access and use data based on the location of the data in the memory array. Also, the reference can be updated so that logical operations can access data that is located in a number of locations in the memory array.

As described in connection with FIG. 1A, the controller 140 may be coupled to sensing circuitry 150 and/or additional logic circuitry 170, including cache, buffers, sense amplifiers, extended row address (XRA) latches, and/or registers, associated with arrays of memory cells via control lines and data paths shown in FIG. 1A. As such, sensing circuitry 150 and logic 170 shown in FIG. 1A can be associated with the arrays of memory cells 130 using data I/Os. The controller 140 may control regular DRAM operations for the arrays such as a read, write, copy, and/or erase operations, etc. Additionally, however, microcode instructions retrieved and executed by the control logic 131 and the microcode function calls received and executed by the sequencer 132 can cause sensing circuitry 150 shown in FIG. 1A to perform additional logical operations such as addition, multiplication, or, as a more specific example, Boolean operations such as an AND, OR, XOR, etc., which are more complex than regular DRAM read and write operations. Hence, in this memory device 120 example, microcode instruction execution and logic operations are performed on the memory device 120.

As such, the control logic 131, sequencer 132, and timing circuitry 133 may operate to generate sequences of operation cycles for a DRAM array. In the memory device 120 example, each sequence may be designed to perform operations, such as a Boolean logic operations AND, OR, XOR, etc., which together achieve a specific function. For example, the sequences of operations may repetitively perform a logical operation for a one (1) bit add in order to calculate a multiple bit sum. Each sequence of operations may be fed into a first in/first out (FIFO) buffer coupled to the timing circuitry 133 to provide timing coordination with the sensing circuity 150 and/or additional logic circuitry 170 associated with the array of memory cells 130, e.g., DRAM arrays, shown in FIG. 1A.

In the example memory device 220 shown in FIG. 1B, the timing circuitry 133 provides timing and provides conflict free access to the arrays from four (4) FIFO queues. In this example, one FIFO queue may support array computation, one may be for Instruction fetch, one for microcode (e.g., Ucode) instruction fetch, and one for DRAM I/O. Both the control logic 131 and the sequencer 132 can generate status information, which is routed back to the bank arbiter via a FIFO interface. The bank arbiter may aggregate this status data and report it back to a host 110 via the HSI.

FIG. 2 is a block diagram of a register 236 in accordance with a number of embodiments of the present disclosure. Register 236 can include a row index (R) 235, a column index (C) 237, and subarray index (S) 239. Register 236 can include a reference to data in memory arrays that includes a row index 235, a column index 237, and a subarray index 239, among other information. The reference of register 236 can include 64 bits of data, where bits 0-9 are the row index 235, bits 10-19 are the column index, and bits 20-29 are the subarray index, for example.

Row index 235 can be used to access data based on the row in the memory array in which the data is stored. The row index 235 in register 236 can be updated by iterating through row indexes to access data stored in horizontal bit vectors in the array of memory cells. The register 236 can be updated by modifying the bits association with a particular index that is part of the reference in the register 236. Column index 237 can be used to access data based on the column in the memory array in which the data is stored. The column index 237 in register 236 can be updated by iterating through columns indexes to access data stored in vertical bit vectors in the array of memory cells. Subarray index 239 can be used to access data based on the subarray in the memory array in which the data is stored. The subarray index 239 in register 236 can be updated by iterating through subarray indexes to access data stored in particular locations of subarrays in the array of memory cells.

FIG. 3 is a block diagram of a set of resolve instructions in accordance with a number of embodiments of the present disclosure. A resolve instruction can be used to update the reference in a register. In the example shown in FIG. 3, a number of resolve instructions 341-0, 341-1, 341-2, 341-3, and 341-4 can be used to iterate through rows of data that are used in logical operations performed on a memory device. Resolve instructions can include 64 bits of data, therefore updating the reference in the register via resolve instructions to access data in a memory array for a logical operation can involve transferring less data than locating data in a memory array via a command from a host, which can include 64 k of data. Resolve instructions can be sent to the sequencer and executed to update the reference in the register on the sequencer and the reference in the register can be used as an operand in logical operations performed on a memory device.

In the example shown in FIG. 3, five resolve instructions are illustrated to show iteration through data stored on five rows in the memory array. Resolve instruction 341-0 can update the reference in the register to access data in a bit vector that is stored in row 0 (R0), column 0 (C0), and subarray (S0) of the memory array. Resolve instruction 341-1 can update the reference in the register to access data in a bit vector that is stored in row 1 (R1), column 0 (C0), and subarray (S0) of the memory array. Resolve instruction 341-2 can update the reference in the register to access data in a bit vector that is stored in row 2 (R2), column 0 (C0), and subarray (S0) of the memory array. Resolve instruction 341-3 can update the reference in the register to access data in a bit vector that is stored in row 3 (R3), column 0 (C0), and subarray (S0) of the memory array. Resolve instruction 341-4 can update the reference in the register to access data in a bit vector that is stored in row 4 (R4), column 0 (C0), and subarray (S0) of the memory array.

In the example shown in FIG. 3, resolve instructions 341-0, 341-1, 341-2, 341-3, and 341-4 can be implement to iterate through data that is stored in consecutive rows in the memory array, although examples are not limited to consecutive rows. For example, accessing data that is stored in vertical bit vectors that include 32 bits may include iterating through the data by accessing data in a bit vector that starts in row 0 and then accessing data in a bit vector that starts in row 32, and so on.

FIG. 4A is a block diagram illustrating a number of bit vectors (e.g., elements) stored as vertical elements in a memory array in accordance with a number of embodiments of the present disclosure. A memory array can include a number of rows (r1-rM) and a number of columns (c1-cN-1), where a bit can be stored at each row/column intersection. In FIG. 4A, a number of 8 bit elements are stored in the memory array. Element 465-0 (Element 0) is a vertical bit vector that has a first bit stored in row 2, column 2 and a last bit stored in row 9, column 2. Element 465-1 (Element 1) is oriented similarly, where the first bit of element 465-1 is in row 2, column 3 and the last bit of element 465-1 is in row 9, column 3. Each column can include an 8 bit element stored in row 2 through row 9 of a column. In FIG. 4A, Element 465-N (Element N) is a vertical bit vector that has a first bit stored in row 10, column 2 and a last bit stored in row 17, column 2. Element 465-N+9 (Element N+9) is oriented similarly, where the first bit of element 465-N+9 is in row 10, column 11 and the last bit of element 465-1 is in row 17, column 11. Each column can include an 8 bit element stored in row 10 through row 17 of a column.

In a number of embodiments, a register can be updated via an instruction (e.g., a resolve instruction) to store a reference to an element in the memory array, wherein the reference in the register can be to each of the elements that start in row 2 of the array, such as elements 465-0, . . . , 465-9. The reference stored in the register can be used in an operation and/or operations, such as an operation with element(s) that start in row 512 and the element(s) referenced in the register. Following the execution of the operation(s) with the element(s) referenced in the register, the register can be updated by a subsequent instruction (e.g., resolve instruction) to be incremented by 8 so that the register stores a reference to element(s) assigned a starting address that is 8 more units than the element previously referenced by the register, such as elements 465-N, . . . , 465-N+9. The element(s) referenced in the updated register can then be used in subsequent operation (s), such as an operation with element(s) that start in row 512.

FIG. 4B is a block diagram illustrating a number of bit vectors (e.g., elements) stored as horizontal elements in a memory array in accordance with a number of embodiments of the present disclosure. A memory array can include a number of rows and a number of columns, where a bit can be stored at each row/column intersection. In FIG. 4B, a number of 16 bit elements are stored in the memory array. Element 465-0 (Element 0) is a vertical bit vector that has a first bit stored in row 2, column 1 and a last bit stored in row 2, column 16. Elements 465-1 (Element 1) and 465-2 (Element 2) are oriented similarly, where the first bit of element 465-1 is in row 2, column 17 and the last bit of element 465-1 is in row 2, column 32 and the first bit of element 465-2 is in row 2, column 33 and the last bit of element 465-2 is in row 2, column 48 (not shown). Each row can include a number of 16 bit elements (k−1 elements) stored in increments of 16 columns, where the number of elements in a row (k−1) is dependent on the number of columns in the array. In FIG. 4B, element 465-K is a horizontal bit vector that has a first bit stored in row 3, column 1 and a last bit stored in row 3, column 16. Elements 465-K+1 (Element K+1) and 465-K+2 (Element K+2) are oriented similarly, where the first bit of element 465-K+1 is in row 2, column 17 and the last bit of element 465-1 is in row 3, column 32 and the first bit of element 465-K+2 is in row 2, column 33 and the last bit of element 465-K+2 is in row 3, column 48 (not shown).

In a number of embodiments, a register can be updated via an instruction (e.g., a resolve instruction) to store a reference to elements in the memory array, wherein the reference in the register can be to each of the elements in row 2 of the array, such as elements 465-0, . . . , 465-K−1. The reference stored in the register can be used in an operation and/or operations, such as an operation with element(s) that start in row 512 and the element(s) referenced in the register. Following the execution of the operation(s) with the element(s) referenced in the register, the register can be updated by a subsequent instruction (e.g., resolve instruction) to be incremented by 1 so that the register stores a reference to elements that start in a row assigned 1 more unit than the element previously referenced by the register, such as elements 465-K, . . . , 465-2K−1. The element referenced in the updated register can then be used in subsequent operation, such as an operation with elements that start in row 512.

FIG. 5 is a schematic diagram illustrating sensing circuitry 550 in accordance with a number of embodiments of the present disclosure. The sensing circuitry 550 can correspond to sensing circuitry 150 shown in FIG. 1.

A memory cell can include a storage element (e.g., capacitor) and an access device (e.g., transistor). For instance, a first memory cell can include transistor 502-1 and capacitor 503-1, and a second memory cell can include transistor 502-2 and capacitor 503-2, etc. In this embodiment, the memory array 530 is a DRAM array of 1T1C (one transistor one capacitor) memory cells, although other embodiments of configurations can be used (e.g., 2T2C with two transistors and two capacitors per memory cell). In a number of embodiments, the memory cells may be destructive read memory cells (e.g., reading the data stored in the cell destroys the data such that the data originally stored in the cell is refreshed after being read).

The cells of the memory array 530 can be arranged in rows coupled by access (word) lines 504-X (Row X), 504-Y (Row Y), etc., and columns coupled by pairs of complementary sense lines (e.g., digit lines DIGIT(D) and DIGIT(D)_ shown in FIG. 5 and DIGIT_0 and DIGIT_0* shown in FIG. 5). The individual sense lines corresponding to each pair of complementary sense lines can also be referred to as digit lines 505-1 for DIGIT (D) and 505-2 for DIGIT (D)_, respectively, or corresponding reference numbers in FIG. 5. Although only one pair of complementary digit lines are shown in FIG. 5, embodiments of the present disclosure are not so limited, and an array of memory cells can include additional columns of memory cells and digit lines (e.g., 4,096, 8,192, 16,384, etc.).

Although rows and columns are illustrated as orthogonally oriented in a plane, embodiments are not so limited. For example, the rows and columns may be oriented relative to each other in any feasible three-dimensional configuration. For example, the rows and columns may be oriented at any angle relative to each other, may be oriented in a substantially horizontal plane or a substantially vertical plane, and/or may be oriented in a folded topology, among other possible three-dimensional configurations.

Memory cells can be coupled to different digit lines and word lines. For example, a first source/drain region of a transistor 502-1 can be coupled to digit line 505-1 (D), a second source/drain region of transistor 502-1 can be coupled to capacitor 503-1, and a gate of a transistor 502-1 can be coupled to word line 504-Y. A first source/drain region of a transistor 502-2 can be coupled to digit line 505-2 (D)_, a second source/drain region of transistor 502-2 can be coupled to capacitor 503-2, and a gate of a transistor 502-2 can be coupled to word line 504-X. A cell plate, as shown in FIG. 5, can be coupled to each of capacitors 503-1 and 503-2. The cell plate can be a common node to which a reference voltage (e.g., ground) can be applied in various memory array configurations.

The memory array 530 is configured to couple to sensing circuitry 550 in accordance with a number of embodiments of the present disclosure. In this embodiment, the sensing circuitry 550 comprises a sense amplifier 506 and a compute component 531 corresponding to respective columns of memory cells (e.g., coupled to respective pairs of complementary digit lines). The sense amplifier 506 can be coupled to the pair of complementary digit lines 505-1 and 505-2. The compute component 531 can be coupled to the sense amplifier 506 via pass gates 507-1 and 507-2. The gates of the pass gates 507-1 and 507-2 can be coupled to operation selection logic 513.

The operation selection logic 513 can be configured to include pass gate logic for controlling pass gates that couple the pair of complementary digit lines un-transposed between the sense amplifier 506 and the compute component 531 and swap gate logic for controlling swap gates that couple the pair of complementary digit lines transposed between the sense amplifier 506 and the compute component 531. The operation selection logic 513 can also be coupled to the pair of complementary digit lines 505-1 and 505-2. The operation selection logic 513 can be configured to control continuity of pass gates 507-1 and 507-2 based on a selected operation.

The sense amplifier 506 can be operated to determine a data value (e.g., logic state) stored in a selected memory cell. The sense amplifier 506 can comprise a cross coupled latch, which can be referred to herein as a primary latch. In the example illustrated in FIG. 5, the circuitry corresponding to sense amplifier 506 comprises a latch 515 including four transistors coupled to a pair of complementary digit lines D 505-1 and (D)_(—) 505-2. However, embodiments are not limited to this example. The latch 515 can be a cross coupled latch (e.g., gates of a pair of transistors) such as n-channel transistors (e.g., NMOS transistors) 527-1 and 527-2 are cross coupled with the gates of another pair of transistors, such as p-channel transistors (e.g., PMOS transistors) 529-1 and 529-2).

In operation, when a memory cell is being sensed (e.g., read), the voltage on one of the digit lines 505-1 (D) or 505-2 (D)_(—) will be slightly greater than the voltage on the other one of digit lines 505-1 (D) or 505-2 (D)_. An ACT signal and an RNL* signal can be driven low to enable (e.g., fire) the sense amplifier 506. The digit lines 505-1 (D) or 505-2 (D)_(—) having the lower voltage will turn on one of the PMOS transistor 529-1 or 529-2 to a greater extent than the other of PMOS transistor 529-1 or 529-2, thereby driving high the digit line 505-1 (D) or 505-2 (D)_(—) having the higher voltage to a greater extent than the other digit line 505-1 (D) or 505-2 (D)_(—) is driven high.

Similarly, the digit line 505-1 (D) or 505-2 (D)_(—) having the higher voltage will turn on one of the NMOS transistor 527-1 or 527-2 to a greater extent than the other of the NMOS transistor 527-1 or 527-2, thereby driving low the digit line 505-1 (D) or 505-2 (D)_(—) having the lower voltage to a greater extent than the other digit line 505-1 (D) or 505-2 (D)_(—) is driven low. As a result, after a short delay, the digit line 505-1 (D) or 505-2 (D)_(—) having the slightly greater voltage is driven to the voltage of the supply voltage V_(CC) through a source transistor, and the other digit line 505-1 (D) or 505-2 (D)_(—) is driven to the voltage of the reference voltage (e.g., ground) through a sink transistor. Therefore, the cross coupled NMOS transistors 527-1 and 527-2 and PMOS transistors 529-1 and 529-2 serve as a sense amplifier pair, which amplify the differential voltage on the digit lines 505-1 (D) and 505-2 (D)_(—) and operate to latch a data value sensed from the selected memory cell.

Embodiments are not limited to the sense amplifier 506 configuration illustrated in FIG. 5. As an example, the sense amplifier 506 can be a current-mode sense amplifier and a single-ended sense amplifier (e.g., sense amplifier coupled to one digit line). Also, embodiments of the present disclosure are not limited to a folded digit line architecture such as that shown in FIG. 5.

The sense amplifier 506 can, in conjunction with the compute component 531, be operated to perform various operations using data from an array as input. In a number of embodiments, the result of an operation can be stored back to the array without transferring the data via a digit line address access and/or moved between banks without using an external data bus (e.g., without firing a column decode signal such that data is transferred to circuitry external from the array and sensing circuitry via local I/O lines). As such, a number of embodiments of the present disclosure can enable performing operations and compute functions associated therewith using less power than various previous approaches. Additionally, since a number of embodiments eliminate the need to transfer data across local and global I/O lines and/or external data buses in order to perform compute functions (e.g., between memory and discrete processor), a number of embodiments can enable an increased (e.g., faster) processing capability as compared to previous approaches.

The sense amplifier 506 can further include equilibration circuitry 514, which can be configured to equilibrate the digit lines 505-1 (D) and 505-2 (D)_. In this example, the equilibration circuitry 514 comprises a transistor 524 coupled between digit lines 505-1 (D) and 505-2 (D)_. The equilibration circuitry 514 also comprises transistors 525-1 and 525-2 each having a first source/drain region coupled to an equilibration voltage (e.g., V_(DD)/2), where V_(DD) is a supply voltage associated with the array. A second source/drain region of transistor 525-1 can be coupled digit line 505-1 (D), and a second source/drain region of transistor 525-2 can be coupled digit line 505-2 (D)_. Gates of transistors 524, 525-1, and 525-2 can be coupled together, and to an equilibration (EQ) control signal line 526. As such, activating EQ enables the transistors 524, 525-1, and 525-2, which effectively shorts digit lines 505-1 (D) and 505-2 (D)_(—) together and to the equilibration voltage (e.g., V_(DD)/2).

Although FIG. 5 shows sense amplifier 506 comprising the equilibration circuitry 514, embodiments are not so limited, and the equilibration circuitry 514 may be implemented discretely from the sense amplifier 506, implemented in a different configuration than that shown in FIG. 5, or not implemented at all.

As described further below, in a number of embodiments, the sensing circuitry 550 (e.g., sense amplifier 506 and compute component 531) can be operated to perform a selected operation and initially store the result in one of the sense amplifier 506 or the compute component 531 without transferring data from the sensing circuitry via a local or global I/O line and/or moved between banks without using an external data bus (e.g., without performing a sense line address access via activation of a column decode signal, for instance).

Performance of operations (e.g., Boolean logical operations involving data values) is fundamental and commonly used. Boolean logical operations are used in many higher level operations. Consequently, speed and/or power efficiencies that can be realized with improved operations, can translate into speed and/or power efficiencies of higher order functionalities.

As shown in FIG. 5, the compute component 531 can also comprise a latch, which can be referred to herein as a secondary latch 564. The secondary latch 564 can be configured and operated in a manner similar to that described above with respect to the primary latch 515, with the exception that the pair of cross coupled p-channel transistors (e.g., PMOS transistors) included in the secondary latch can have their respective sources coupled to a supply voltage (e.g., V_(DD)), and the pair of cross coupled n-channel transistors (e.g., NMOS transistors) of the secondary latch can have their respective sources selectively coupled to a reference voltage (e.g., ground), such that the secondary latch is continuously enabled. The configuration of the compute component 531 is not limited to that shown in FIG. 5, and various other embodiments are feasible.

The memory device can include a sensing stripe configured to include a number of a plurality of sense amplifiers and compute components (e.g., 606-0, 606-1, . . . , 606-7 and 631-0, 631-1, . . . , 631-7, respectively, as shown in FIG. 6) that can correspond to a number of the plurality of columns (e.g., 622 in FIGS. 6 and 505-1 and 505-2 in FIG. 5) of the memory cells, where the number of sense amplifiers and/or compute components can be selectably coupled to the plurality of shared I/O lines (e.g., via column select circuitry 658-1 and 658-2). The column select circuitry can be configured to selectably sense data in a particular column of memory cells of a subarray by being selectably coupled to a plurality of (e.g., four, eight, and sixteen, among other possibilities) sense amplifiers and/or compute components.

As described herein, the array of memory cells can include an implementation of DRAM memory cells where the controller is configured, in response to a command, to move (e.g., copy, transfer, and/or transport) data from the source location to the destination location via a shared I/O line. According to embodiments, the data can be moved as described in connection with FIG. 1.

As described herein, the apparatus can be configured to move (e.g., copy, transfer, and/or transport) data from a source location, including a particular row (e.g., 619 in FIG. 6) and column address associated with a first number of sense amplifiers and compute components) to a shared I/O line. In addition, the apparatus can be configured to move the data to a destination location, including a particular row and column address associated with a second number of sense amplifiers and compute components. As the reader will appreciate, each shared I/O line (e.g., 655) can actually include a complementary pair of shared I/O lines (e.g., shared I/O line and shared I/O line* as shown in the example configuration of FIG. 5). In some embodiments described herein, 2048 shared I/O lines (e.g., complementary pairs of shared I/O lines) can be configured as a 2048 bit wide shared I/O line.

FIG. 6 is a schematic diagram illustrating sensing circuitry capable of implementing an XOR logical operation in accordance with a number of embodiments of the present disclosure. FIG. 6 shows a sense amplifier 606 coupled to a pair of complementary sense lines 605-1 and 605-2, and a compute component 631 coupled to the sense amplifier 606 via pass gates 607-1 and 607-2. The sense amplifier 606 shown in FIG. 6 can correspond to sense amplifier 506 shown in FIG. 5. The compute component 631 shown in FIG. 6 can correspond to sensing circuitry 150, including compute component, shown in FIG. 1A, for example. The logical operation selection logic 613 shown in FIG. 6 can correspond to logical operation selection logic 513 shown in FIG. 5.

The gates of the pass gates 607-1 and 607-2 can be controlled by a logical operation selection logic signal, Pass. For example, an output of the logical operation selection logic can be coupled to the gates of the pass gates 607-1 and 607-2. The compute component 631 can comprise a loadable shift register configured to shift data values left and right.

According to the embodiment illustrated in FIG. 6, the compute components 631 can comprise respective stages (e.g., shift cells) of a loadable shift register configured to shift data values left and right. For example, as illustrated in FIG. 6, each compute component 631 (e.g., stage) of the shift register comprises a pair of right-shift transistors 681 and 686, a pair of left-shift transistors 689 and 690, and a pair of inverters 687 and 688. The signals PHASE 1R, PHASE 2R, PHASE 1L, and PHASE 2L can be applied to respective control lines 682, 683, 691 and 692 to enable/disable feedback on the latches of the corresponding compute components 631 in association with performing logical operations and/or shifting data in accordance with embodiments described herein.

The sensing circuitry shown in FIG. 6 also shows a logical operation selection logic 613 coupled to a number of logic selection control input control lines, including ISO, TF, TT, FT, and FF. Selection of a logical operation from a plurality of logical operations is determined from the condition of logic selection control signals on the logic selection control input control lines, as well as the data values present on the pair of complementary sense lines 605-1 and 605-2 when the isolation transistors 650-1 and 650-2 are enabled via the ISO control signal being asserted.

According to various embodiments, the logical operation selection logic 613 can include four logic selection transistors: logic selection transistor 662 coupled between the gates of the swap transistors 642 and a TF signal control line, logic selection transistor 652 coupled between the gates of the pass gates 607-1 and 607-2 and a TT signal control line, logic selection transistor 654 coupled between the gates of the pass gates 607-1 and 607-2 and a FT signal control line, and logic selection transistor 664 coupled between the gates of the swap transistors 642 and a FF signal control line. Gates of logic selection transistors 662 and 652 are coupled to the true sense line through isolation transistor 650-1 (having a gate coupled to an ISO signal control line). Gates of logic selection transistors 664 and 654 are coupled to the complementary sense line through isolation transistor 650-2 (also having a gate coupled to an ISO signal control line).

Data values present on the pair of complementary sense lines 605-1 and 605-2 can be loaded into the compute component 631 via the pass gates 607-1 and 607-2. The compute component 631 can comprise a loadable shift register.

When the pass gates 607-1 and 607-2 are OPEN, data values on the pair of complementary sense lines 605-1 and 605-2 are passed to the compute component 631 and thereby loaded into the loadable shift register. The data values on the pair of complementary sense lines 605-1 and 605-2 can be the data value stored in the sense amplifier 606 when the sense amplifier is fired. The logical operation selection logic signal, Pass, is high to OPEN the pass gates 607-1 and 607-2.

The ISO, TF, TT, FT, and FF control signals can operate to select a logical function to implement based on the data value (“B”) in the sense amplifier 606 and the data value (“A”) in the compute component 631. In particular, the ISO, TF, TT, FT, and FF control signals are configured to select the logical function to implement independent from the data value present on the pair of complementary sense lines 605-1 and 605-2 (although the result of the implemented logical operation can be dependent on the data value present on the pair of complementary sense lines 605-1 and 605-2. That is, the ISO, TF, TT, FT, and FF control signals select the logical operation to implement directly since the data value present on the pair of complementary sense lines 605-1 and 605-2 is not passed through logic to operate the gates of the pass gates 607-1 and 607-2.

Additionally, FIG. 6 shows swap transistors 642 configured to swap the orientation of the pair of complementary sense lines 605-1 and 605-2 between the sense amplifier 606 and the compute component 631. When the swap transistors 642 are OPEN, data values on the pair of complementary sense lines 605-1 and 605-2 on the sense amplifier 606 side of the swap transistors 642 are oppositely-coupled to the pair of complementary sense lines 605-1 and 605-2 on the compute component 631 side of the swap transistors 642, and thereby loaded into the loadable shift register of the compute component 631.

The logical operation selection logic signal Pass can be activated (e.g., high) to OPEN the pass gates 607-1 and 607-2 (e.g., conducting) when the ISO control signal line is activated and either the TT control signal is activated (e.g., high) and data value on the true sense line is “1” or the FT control signal is activated (e.g., high) and the data value on the complement sense line is “1.”

The data value on the true sense line being a “1” OPENs logic selection transistors 652 and 662. The data value on the complimentary sense line being a “1” OPENs logic selection transistors 654 and 664. If the ISO control signal or either the respective TT/FT control signal or the data value on the corresponding sense line (e.g., sense line to which the gate of the particular logic selection transistor is coupled) is not high, then the pass gates 607-1 and 607-2 will not be OPENed by a particular logic selection transistor.

The logical operation selection logic signal Pass* can be activated (e.g., high) to OPEN the swap transistors 642 (e.g., conducting) when the ISO control signal line is activated and either the TF control signal is activated (e.g., high) and data value on the true sense line is “1,” or the FF control signal is activated (e.g., high) and the data value on the complement sense line is “1.” If either the respective control signal or the data value on the corresponding sense line (e.g., sense line to which the gate of the particular logic selection transistor is coupled) is not high, then the swap transistors 642 will not be OPENed by a particular logic selection transistor.

The Pass* control signal is not necessarily complementary to the Pass control signal. It is possible for the Pass and Pass* control signals to both be activated or both be deactivated at the same time. However, activation of both the Pass and Pass* control signals at the same time shorts the pair of complementary sense lines together, which may be a disruptive configuration to be avoided.

The sensing circuitry illustrated in FIG. 6 is configured to select one of a plurality of logical operations to implement directly from the four logic selection control signals (e.g., logical operation selection is not dependent on the data value present on the pair of complementary sense lines). Some combinations of the logic selection control signals can cause both the pass gates 607-1 and 607-2 and swap transistors 642 to be OPEN at the same time, which shorts the pair of complementary sense lines 605-1 and 605-2 together. According to a number of embodiments of the present disclosure, the logical operations which can be implemented by the sensing circuitry illustrated in FIG. 6 can be the logical operations summarized in the logic tables shown in FIG. 7.

FIG. 7 is a logic table illustrating selectable logic operation results implemented by a sensing circuitry shown in FIG. 6 in accordance with a number of embodiments of the present disclosure. The four logic selection control signals (e.g., TF, TT, FT, and FF), in conjunction with a particular data value present on the complementary sense lines, can be used to select one of plural logical operations to implement involving the starting data values stored in the sense amplifier 606 and compute component 631. The four control signals, in conjunction with a particular data value present on the complementary sense lines, controls the continuity of the pass gates 607-1 and 607-2 and swap transistors 642, which in turn affects the data value in the compute component 631 and/or sense amplifier 606 before/after firing. The capability to selectably control continuity of the swap transistors 642 facilitates implementing logical operations involving inverse data values (e.g., inverse operands and/or inverse result), among others.

Logic Table 7-1 illustrated in FIG. 7 shows the starting data value stored in the compute component 631 shown in column A at 744, and the starting data value stored in the sense amplifier 606 shown in column B at 745. The other 3 column headings in Logic Table 7-1 refer to the continuity of the pass gates 607-1 and 607-2, and the swap transistors 642, which can respectively be controlled to be OPEN or CLOSED depending on the state of the four logic selection control signals (e.g., TF, TT, FT, and FF), in conjunction with a particular data value present on the pair of complementary sense lines 605-1 and 605-2. The “Not Open” column 756 corresponds to the pass gates 607-1 and 607-2 and the swap transistors 642 both being in a non-conducting condition, the “Open True” column 770 corresponds to the pass gates 607-1 and 607-2 being in a conducting condition, and the “Open Invert” column 773 corresponds to the swap transistors 642 being in a conducting condition. The configuration corresponding to the pass gates 607-1 and 607-2 and the swap transistors 642 both being in a conducting condition is not reflected in Logic Table 7-1 since this results in the sense lines being shorted together.

Via selective control of the continuity of the pass gates 607-1 and 607-2 and the swap transistors 642, each of the three columns of the upper portion of Logic Table 7-1 can be combined with each of the three columns of the lower portion of Logic Table 7-1 to provide 3×3=9 different result combinations, corresponding to nine different logical operations, as indicated by the various connecting paths shown at 775. The nine different selectable logical operations that can be implemented by the sensing circuitry, e.g., 150 in FIG. 1A, are summarized in Logic Table 7-2 illustrated in FIG. 7, including an XOR logical operation.

The columns of Logic Table 7-2 illustrated in FIG. 7 show a heading 780 that includes the state of logic selection control signals. For example, the state of a first logic selection control signal is provided in row 776, the state of a second logic selection control signal is provided in row 777, the state of a third logic selection control signal is provided in row 778, and the state of a fourth logic selection control signal is provided in row 779. The particular logical operation corresponding to the results is summarized in row 747.

While example embodiments including various combinations and configurations of sensing circuitry, sense amplifiers, compute component, dynamic latches, isolation devices, and/or shift circuitry have been illustrated and described herein, embodiments of the present disclosure are not limited to those combinations explicitly recited herein. Other combinations and configurations of the sensing circuitry, sense amplifiers, compute component, dynamic latches, isolation devices, and/or shift circuitry disclosed herein are expressly included within the scope of this disclosure.

Although specific embodiments have been illustrated and described herein, those of ordinary skill in the art will appreciate that an arrangement calculated to achieve the same results can be substituted for the specific embodiments shown. This disclosure is intended to cover adaptations or variations of one or more embodiments of the present disclosure. It is to be understood that the above description has been made in an illustrative fashion, and not a restrictive one. Combination of the above embodiments, and other embodiments not specifically described herein will be apparent to those of skill in the art upon reviewing the above description. The scope of the one or more embodiments of the present disclosure includes other applications in which the above structures and methods are used. Therefore, the scope of one or more embodiments of the present disclosure should be determined with reference to the appended claims, along with the full range of equivalents to which such claims are entitled.

In the foregoing Detailed Description, some features are grouped together in a single embodiment for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the disclosed embodiments of the present disclosure have to use more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive subject matter lies in less than all features of a single disclosed embodiment. Thus, the following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separate embodiment. 

What is claimed is:
 1. An apparatus, comprising: an array of memory cells; and a controller coupled to the array of memory cells configured to: perform logical operations on data stored in the array of memory cells using a register that is updated to access the data stored in the array of memory cells.
 2. The apparatus of claim 1, wherein the controller is configured to store a reference to an operand in the register used while performing the logical operations.
 3. The apparatus of claim 1, wherein the controller is configured to include a reference to the data stored in the array of memory cells in the register.
 4. The apparatus of claim 1, wherein the controller is configured to update the register to access the data stored in the array of memory cells based on a location of the data stored in the array of memory cells.
 5. The apparatus of claim 1, wherein the controller is configured to update the register while performing the logical operations by iterating through the data based on a location of the data.
 6. The apparatus of claim 1, wherein the controller is configured to update the resister to iterate through rows in which the data is stored in the array of memory cells.
 7. The apparatus of claim 1, wherein the controller is configured to update the resister to iterate through columns in which the data is stored in the array of memory cells.
 8. The apparatus of claim 1, wherein the controller is configured to update the resister to iterate through subarrays in which the data is stored in the array of memory cells.
 9. An apparatus, comprising: an array of memory cells; and a controller coupled to the array of memory cells configured to: update a register to access data stored in the array of memory cells, wherein the register is used while performing logical operations using the data stored in the array of memory.
 10. The apparatus of claim 9, wherein an instruction is used to update the register.
 11. The apparatus of claim 10, wherein the instruction includes 64 bits.
 12. The apparatus of claim 9, wherein the register is updated by performing a Boolean operation to access data stored as bit vectors in the array of memory cells.
 13. The apparatus of claim 9, wherein the register is updated to iterate through data stored in the array of memory cells.
 14. The apparatus of claim 9, wherein the register is updated to access data stored as horizontal bit vectors in the array of memory cells.
 15. The apparatus of claim 9, wherein the register is updated to access data stored as vertical bit vectors in the array of memory cells.
 16. The apparatus of claim 9, wherein the register is updated to access data stored as bit vectors in particular subarrays in the array of memory cells.
 17. A method for operating a memory device, comprising: performing logical operations on data stored in the memory device, wherein performing the logical operations include: storing a reference to an operand for the logical operations in a register; and updating a reference in the register to access the data stored in the memory device.
 18. The method of claim 17, wherein updating the reference includes updating a row index of the reference in the register.
 19. The method of claim 17, wherein updating the reference includes updating a column index of the reference in the register.
 20. The method of claim 17, wherein the method includes updating a subarray index of the reference in the register.
 21. The method of claim 17, wherein updating the reference includes updating the reference in the register without intervention from a host.
 22. The method of claim 17, wherein the method includes updating the reference in the register to iterate through data stored in memory.
 23. The method of claim 17, wherein the method includes updating the reference via arithmetic logic unit (ALU) circuitry.
 24. A method for operating a memory device, comprising: updating a reference in a register to access data stored in the memory device based on a location of the data stored in the memory device; and performing logical operations using the data stored in the memory device, wherein the reference in the register is an operand in the logical operations.
 25. The method of claim 24, wherein updating the reference includes iterating through data stored in the memory device based on the location of the data.
 26. The method of claim 25, wherein the method includes iteration through the data stored in the memory device by incrementing the reference in the register.
 27. The method of claim 25, wherein the method includes iteration through the data stored in the memory device by decrementing the reference in the register.
 28. The method of claim 24, wherein updating the reference includes iterating through data stored in vertical bit vectors.
 29. The method of claim 24, wherein updating the reference includes iterating through data stored in horizontal bit vectors. 